Minimum radius for industrial sidings in 00-SF

[Andy Reichert]

I'd start the evaluation for a track with one check rail, set at the 1 mm gap and a train with the chunkiest wheels. The minimum radius will depend rather on the thickness of the flanges and, on a vehicle with three or more axles, the amount of side play. You might try getting a piece of number 1 radius Setrack and tack in a check rail inside the inner rail. If this doesn't foul you could try again with a bit of flexi track, cut all the webbing so it will go down to saucer size if need be. When you get one or more flanges binding on the inner rail, back off a bit. Rebuild as a curve using copper clad with minimal sleepering. If it fouls, you can dismantle it and rebuilt it without wasting material.

 

I'd be intrigued to see what you find as my layout will have a 'dockside' siding, though at the moment the radius needs to be around 30 inches widening out to a straight and I don't envisage a problem.

 

The inset track which Andy makes relies on the very tips of the wheel flanges sitting in the rail groove, with the wheel treads in free space, and it should cope with tighter curves. However I haven't worked out how to bend a straight length to fit the layout, and the fixed radii are rather tramway-like.

 

- Richard.

 

Just to clarify the dimensions for the paved track. Normal RTR wheels sit with 50% of their flange depth down inside the girder rail groove. P:87 and P4 wheels run on their tyres as normal.

 

In order to avoid infinite tooling costs, I've made the curved sections in 2" radius steps from 8" up to 18" so far. But I will probably add a couple of the larger, more typical model railway radii in the not too distant future. I have the HOm people with Euro double track track spacing to help first.

 

Andy

[rue_d_etropal]

Hi,

just wondering how big an area is intended for industrial/dockyard area. I ask as I am the person who has developed the 3D printed inset track system(reviewed in March Model Rail magazine). Possibly not fine enough scale for some, but one of the great things about adding such a scene is that it does not need to take up much space, which is why I have used setrack geometry initially. I am considering a version to use finer rail. I also have designed a working wagon turntable , which could also be redesigned for finer rail section.

[47137]

Hi,

just wondering how big an area is intended for industrial/dockyard area.

On my layout, the industrial dock area will be a triangular shape about 37 x 15 inches. I planned it for Peco Streamline points with a minimum radius of about 24 inches, but at the moment I am redesigning it for home-made points in 00-SF. This is the largest scene of a layout with three other "areas of interest".

 

- Richard.

[rue_d_etropal]

thanks Richard.

Sounds interesting but doesn't sound like it will be a complex design. Wagon turntables would definitely add interest and a steady hand on throttle.

[nswgr1855]

Ok, to get this back on topic...

 

Thanks for all your replies.  As far as pointwork goes, it seems I can get away with pretty sharp radius, by gauge-widening to standard 00, as long as through the crossing Vs are more-or-less straight, as "mighbe" suggested above, as long as I avoid curviform V-crossings, I should be ok, down to R1 settrack equivalent, or even a bit tighter.

 

Now, to bowl a googlie.  I am also thinking about at least some of the sidings being inset, possibly with a wagon turntable at the end.  This inset track will need checkrails on both sides, and I want to do these to 00-sf, to preserve the finer-looking checkrail gap.

 

Ok, the prototype (as PatB said at Gloucester dock) can do R1 setrack, but the prototype has much finer wheel flanges than 00 RTR.

 

What minimum radius can I use for 00-sf double-checkrailed track?

 

My experience is you do not need to gauge widen 00-SF other than adding a small value for a practical tolerance. The 00-SF wheel track clearance at 16.2mm track gauge is no less than the prototype clearance. The reason why we can go smaller than prototype minimum radius is our models have more side play compared to the prototype. The minimum practical radius taking into account body mounted model couplings can be found by using the AMRA minimum radius standard http://www.amra.asn.au/standards.htm. For those using buffers and link couplers you need to stick to the minimum prototype curve. If this is not known I would suggest using a radius = 5 times the length of your longest locomotive or carriage. 

 

Cheers,

Terry Flynn

[Andy Reichert]

My experience is you do not need to gauge widen 00-SF other than adding a small value for a practical tolerance. The 00-SF wheel track clearance at 16.2mm track gauge is no less than the prototype clearance. The reason why we can go smaller than prototype minimum radius is our models have more side play compared to the prototype. The minimum practical radius taking into account body mounted model couplings can be found by using the AMRA minimum radius standard http://www.amra.asn.au/standards.htm. For those using buffers and link couplers you need to stick to the minimum prototype curve. If this is not known I would suggest using a radius = 5 times the length of your longest locomotive or carriage. 

 

Cheers,

Terry Flynn

 

Martin,

 

I think you really need to not ignore this one. Does 00-SF narrower track gauge have a greater min radius than 00, or doesn't it ??????

 

Andy

[martin_wynne]

Martin,

 

I think you really need to not ignore this one. Does 00-SF narrower track gauge have a greater min radius than 00, or doesn't it ??????

 

Andy

 

Why do I have to do the ignoring? How about someone else ignoring it instead?

 

Martin.

[Andy Reichert]

Why do I have to do the ignoring? How about someone else ignoring it instead?

 

Martin.

 

It's your (sensible) claim for 00-SF he's outright denying.

 

Andy

[martin_wynne]

Or even the not ignoring.

 

00-SF is derived from EM, and shares the same radius restrictions.

 

For UK-style rolling stock, buffers and couplings, I suggest a minimum radius for 16.2mm gauge of 30" / 750mm.

 

Below that the gauge needs to be progressively widened until you reach 16.5mm for train-set curves at say 24" radius and below.

 

It does very much depend on the actual stock, wheelbase, side-play, buffer lengths, type of couplings, and 97 other variables.

 

The EMGS have a detailed manual available to members. For anyone modelling in 00-SF membership of the EMGS would be worthwhile: http://www.emgs.org/

 

In practice I'm not sure modellers intending curves below 30" / 750mm should be contemplating 00-SF any more than they would EM, except perhaps for industrial / light railways / shunting planks - where the type of rolling-stock is restricted.

 

It's your (sensible) claim for 00-SF he's outright denying.

 

Why do you keep blaming me for 00-SF?

 

Martin.

[47137]

On my layout, the industrial dock area will be a triangular shape about 37 x 15 inches. I planned it for Peco Streamline points with a minimum radius of about 24 inches, but at the moment I am redesigning it for home-made points in 00-SF. This is the largest scene of a layout with three other "areas of interest".

 

Below is a rather unflattering shot of my layout. I started out with the intention to use Peco points throughout, then decided to try for 00-SF in the quayside area, this became HO-SF, and in the end I settled on something in between - a 1.1 mm crossing flangeway with a 15.2 mm check gauge. The straight part of my inset track is true to H0-SF.

 

I remember a discussion with a plumber many years ago, on the subject of compression fittings. The essence of this was, "if you prepare the pipes carefully and make the joint up dry, it probably won't leak ... but if you use a tiny smear of a jointing compound, it will never leak". In a similar vein, I suggest that if you want to use curve radii below 30 inches and going down to 26 inches radii or so, ease the crossing flangeways out to 1.1 mm and the track will work. Below this dimension of c.26 inches, you would be better off with plain-vanilla 1.3 mm gaps all round.

 

For any curve below c. 30 inches, the calculations which Martin posted on 24th March show the beginning of gauge widening and the aesthetic benefit of 00-SF starts to slip away in every location where you need to put more than one check rail.

 

I have put a steel rule in my photo. The tight curve into the siding with the inspection pit is a copy of Hornby number 2 radius - sorry but it was the only arrangement that would fit. Aesthetically, it looks "tight" from a usual viewing angle, so it helps the turnouts nearby look more gentle than they really are. Practically, only a small light engine will ever use it. Well that's my excuse!

 

My own conclusion is that HO-SF is an excellent choice for turnouts which represents the typical geometry of a real main line and its associated sidings. For a my own compact industrial layout, I feel I have improved on RTR standards for tighter curves, but not as far as HO-SF.

 

- Richard.

 

Edit: The blue pins show the positions of the tiebars of the intended Peco turnouts.

[martin_wynne]

I suggest that if you want to use curve radii below 30 inches and going down to 26 inches radii or so, ease the crossing flangeways out to 1.1 mm and the track will work. Below this dimension of c.26 inches, you would be better off with plain-vanilla 1.3 mm gaps all round.

 

I suggest you don't do that, or at least not if you want to call it 00-SF as in this topic title.

 

On what track gauge are you doing this?

 

Just to repeat for the 500th time:

 

You must keep the check gauge constant at 15.2mm if you don't want wheel flanges to hit the nose of the vee.

 

You must not increase the crossing flangeway gap beyond 1.0mm if you don't want kit wheels to fall into it.

 

What you call "plain-vanilla 1.3 mm gaps all round" is 00-BF and not 00-SF and requires: 16.5mm track gauge and not 16.2mm gauge if you are referring to the check rail gap, and only RTR wheels if you are referring to the crossing flangeway.

 

All you need to do for sharp curves is increase the track gauge, and leave the check rails and crossing flangeway gap as set by the 00-SF gauge tools. Or simply not use 00-SF.

 

If you have devised your own standard using 1.1mm flangeways on 16.3mm track gauge, that's fine. It may work very well. But PLEASE don't call it 00-SF or H0-SF because it isn't either of those. PLEASE invent your own name for it.

 

Mixing things up just confuses everyone and is the reason some folks just despair of ever understanding.

 

regards,

 

Martin.

[Andy Reichert]

Why do you keep blaming me for 00-SF?

 

Martin.

 

You're the one telling us how much other people like it.

 

Andy

[nswgr1855]

I suggest you don't do that, or at least not if you want to call it 00-SF as in this topic title.

 

On what track gauge are you doing this?

 

Just to repeat for the 500th time:

 

You must keep the check gauge constant at 15.2mm if you don't want wheel flanges to hit the nose of the vee.

 

You must not increase the crossing flangeway gap beyond 1.0mm if you don't want kit wheels to fall into it.

 

What you call "plain-vanilla 1.3 mm gaps all round" is 00-BF and not 00-SF and requires: 16.5mm track gauge and not 16.2mm gauge if you are referring to the check rail gap, and only RTR wheels if you are referring to the crossing flangeway.

 

All you need to do for sharp curves is increase the track gauge, and leave the check rails and crossing flangeway gap as set by the 00-SF gauge tools. Or simply not use 00-SF.

 

If you have devised your own standard using 1.1mm flangeways on 16.3mm track gauge, that's fine. It may work very well. But PLEASE don't call it 00-SF or H0-SF because it isn't either of those. PLEASE invent your own name for it.

 

Mixing things up just confuses everyone and is the reason some folks just despair of ever understanding.

 

regards,

 

Martin.

 

Hello Martin,

 

If you use the definition of 00-SF of 16.2mm minimum track gauge and 1mm minimum flange way then there is no need for a new name in my view.Track gauged to 16.3mm and 1.1mm flangeways is still 'close enough' as long as the check gauge is the same at 15.2mm. The 1.1 flange way is starting to get into the small (but not noticeable) wheel drop zone for the finer wheels.

 

Cheers,

 

Terry Flynn. 

[nswgr1855]

Martin,

 

I think you really need to not ignore this one. Does 00-SF narrower track gauge have a greater min radius than 00, or doesn't it ??????

 

Andy

Andy,

 

For any properly designed wheel and track standard the minimum radius is determined by the type of equipment that is run on the model. The AMRA minimum radius standard http://www.amra.asn.au/standards.htm gives you the minimum radius for lengths of locomotives and carriages and will work for both 00-SF and 00. 

 

Terry Flynn.

[hayfield]

You're the one telling us how much other people like it.

 

Andy

 

 

Andy

 

You are oh so wrong, many on this forum are clearly stating that 00sf works for them, not only in performance but visually. 00 gauge (in all its incarnations) is a compromise, its just which compromise you prefer.

 

Back to the OP's original question, which is basically "can I use a more visually better looking turnout on a small layout with very tight radius turnouts ?" I am certain the poster would like many constructive replies to his question. But not someone ranting on about not liking the gauge, which is not answering his question at all

[Arthur]

Andy

 

You are oh so wrong, many on this forum are clearly stating that 00sf works for them, not only in performance but visually. 00 gauge (in all its incarnations) is a compromise, its just which compromise you prefer.

 

Exactly John, "it's just which compromise you prefer", it never ceases to amaze me that, where 4mm track is concerned, how others feel the need to impose their views of what's 'right'. Just live and let live, please.

[martin_wynne]

If you use the definition of 00-SF of 16.2mm minimum track gauge and 1mm minimum flange way then there is no need for a new name in my view.Track gauged to 16.3mm and 1.1mm flangeways is still 'close enough' as long as the check gauge is the same at 15.2mm. The 1.1 flange way is starting to get into the small (but not noticeable) wheel drop zone for the finer wheels.

 

Hi Terry,

 

I disagree.

 

1.1mm flangeway does not fall within the 00-SF definition. The crossing flangeway should be a close fit on a 1.0mm gauge shim. That means it may perhaps be a fraction more than 1.0mm, say 1.02mm max, or about 1 thou over. Not 1.1mm which would be a very loose fit (4 thou over, or the thickness of office paper).

 

The reason it is important is that the whole point and purpose of "EM minus 2" (00-SF) is to provide full support for kit wheels and allow for modelling a prototypical blunt nose on the vee.

 

For bullhead track than means 3/4" blunt nose which scales to 0.25mm at 4mm/ft scale. So the gap across in front of the nose will be 1.0mm + 0.25mm + 1.0mm = 2.25mm. i.e. just enough to fully support kit wheels 2.3mm wide.

 

Ideally with kit wheels we could make the flangeway somewhat less than 1.0mm, but then we would lose the option to run RTR wheels at the same time.

 

With 1.1mm flangeways the gap across in front of the vee will be 2.45mm, which is wider than 2.3mm and kit wheels may therefore drop a little into it with a bump. Not as badly as on 00-BF of course, but still enough to cause rough running. The only way to assure full support with 1.1mm flangeways would be to use a sharp nose on the vee. Which is not prototypical and looks daft to an engineer's eye.

 

Adopting a standard of 16.3mm track gauge with 1.1mm flangeways is perfectly acceptable if a wider tolerance on RTR back-to-backs is more important than full support for kit wheels (or sharp-nose vees are acceptable). But it is NOT 00-SF.

 

It is just not fair to beginners to change things and keep the same name as before. It leads to utter confusion and I believe this is the thrust of Andy R's objection to your AMRA standards.

 

I'm happy to include 16.3mm track gauge with 1.1mm flangeways in Templot, but it must have its own name -- it's not 00-SF. I would suggest 00-MF "modified fine".

 

regards,

 

Martin.

[Andy Reichert]

Hi Terry,

 

I disagree.

 

1.1mm flangeway does not fall within the 00-SF definition. The crossing flangeway should be a close fit on a 1.0mm gauge shim. That means it may perhaps be a fraction more than 1.0mm, say 1.02mm max, or about 1 thou over. Not 1.1mm which would be a very loose fit (4 thou over, or the thickness of office paper).

 

The reason it is important is that the whole point and purpose of "EM minus 2" (00-SF) is to provide full support for kit wheels and allow for modelling a prototypical blunt nose on the vee.

 

For bullhead track than means 3/4" blunt nose which scales to 0.25mm at 4mm/ft scale. So the gap across in front of the nose will be 1.0mm + 0.25mm + 1.0mm = 2.25mm. i.e. just enough to fully support kit wheels 2.3mm wide.

 

Ideally with kit wheels we could make the flangeway somewhat less than 1.0mm, but then we would lose the option to run RTR wheels at the same time.

 

With 1.1mm flangeways the gap across in front of the vee will be 2.45mm, which is wider than 2.3mm and kit wheels may therefore drop a little into it with a bump. Not as badly as on 00-BF of course, but still enough to cause rough running. The only way to assure full support with 1.1mm flangeways would be to use a sharp nose on the vee. Which is not prototypical and looks daft to an engineer's eye.

 

Adopting a standard of 16.3mm track gauge with 1.1mm flangeways is perfectly acceptable if a wider tolerance on RTR back-to-backs is more important than full support for kit wheels (or sharp-nose vees are acceptable). But it is NOT 00-SF.

 

It is just not fair to beginners to change things and keep the same name as before. It leads to utter confusion and I believe this is the thrust of Andy R's objection to your AMRA standards.

 

I'm happy to include 16.3mm track gauge with 1.1mm flangeways in Templot, but it must have its own name -- it's not 00-SF. I would suggest 00-MF "modified fine".

 

regards,

 

Martin.

 

FINALLY!!!!!!!!   

 

Andy

 

PS. Now will you object to Terry's ABSURD claim that narrowing the gauge does not affect the minimum radius of the same RTR locomotive.

[martin_wynne]

FINALLY!!!!!!!!   

 

Andy

 

PS. Now will you object to Terry's ABSURD claim that narrowing the gauge does not affect the minimum radius of the same RTR locomotive.

 

Hi Andy,

 

FINALLY what? Sometimes your posts are very hard to follow. Or else I'm being thick.

 

Where has Terry made that claim? It depends whether the radius limit is caused by the wheels, or other factors such as couplings, buffer length, platform clearance, etc.

 

In any event, no-one narrows the gauge. Who would do that? In 00-SF we widen it on sharp curves, as on the prototype. In practice it is necessary only on the sharpest curves for industrial railways, etc.

 

Martin.

[Andy Reichert]

Andy

 

You are oh so wrong, many on this forum are clearly stating that 00sf works for them, not only in performance but visually. 00 gauge (in all its incarnations) is a compromise, its just which compromise you prefer.

 

Back to the OP's original question, which is basically "can I use a more visually better looking turnout on a small layout with very tight radius turnouts ?" I am certain the poster would like many constructive replies to his question. But not someone ranting on about not liking the gauge, which is not answering his question at all

 

I'm always open to someone showing where my basic arithmetic is wrong. That's the only criteria I use determine when someone is making false claims. I try my darnest to never give an unsupported opinion.

 

There are compromises which work in limited circumstances, but then someone comes along and says "but this item doesn't work like everything else". And that's where the "But it's works on my layout" reasoning falls completely down.

 

You want a current example?

 

Wright writes. . . . posting # 4521

 

 

My stock uses a mixture of RTR, Gibson, Ultrascale and Romfort/Markits wheels. I can safely that all of these have coped with Peco Code 75 pointwork (plus C+L plain track) without difficulty, but the one type of wheel I did have problems with was the DCC Concepts coach wheels, with the built-in pickup system. These are a good product but the wheel profile is very fine and despite fiddling with the back to backs, I couldn't get them to track through Peco turnouts reliably. In the end I used the plastikard method above, and after some trial and error I got the DCC Concepts wheels to work as well as the others. The good news is that almost everything else still runs through the points without trouble, but in one or two cases I had to swap an old wheelset or ease out a back to back.

 

-----------------

 

 

This is an unknowing mixing standards issue again. Using 00-SF is one way of solving the problem of (apparently) DCC Concepts not realizing (or caring) their problem of selling the same profile

"fine" wheels for 00 as for EM.

 

But as DCC concepts told me way back - "most of my customer haven't complained".

 

Andy

[Andy Reichert]

Hi Andy,

 

FINALLY what? Sometimes your posts are very hard to follow. Or else I'm being thick.

 

Where has Terry made that claim? It depends whether the radius limit is caused by the wheels, or other factors such as couplings, buffer length, platform clearance, etc.

 

In any event, no-one narrows the gauge. Who would do that? In 00-SF we widen it on sharp curves, as on the prototype. In practice it is necessary only on the sharpest curves for industrial railways, etc.

 

Martin.

 

Post # 39 as I said before - Precis - Min radius is caused by  equipment. So is the same both 00 and 00-SF.

 

The latter sentence is invalid mathematically and in practice.

 

Andy

[martin_wynne]

This is an unknowing mixing standards issue again. Using 00-SF is one way of solving the problem of (apparently) DCC Concepts not realizing (or caring) their problem of selling the same profile

"fine" wheels for 00 as for EM.

 

Hi Andy,

 

All kit wheel makers in the UK sell the same wheels for 00 as for EM. Or at least, I don't know any who don't. Some of them, e.g. Alan Gibson, set them at 14.8mm back-to-back for DOGA Fine (on which they are ok) but fail to mention that they won't run on 00-BF or Peco (they are too narrow).

 

That's the primary reason for adopting "EM minus 2" (00-SF) -- it allows these EM wheels (ideally closed up to 14.6mm back-to-back) and unmodified RTR wheels to run on the same track. If Tony Wright was to adopt 00-SF he would discover this for himself.

 

regards,

 

Martin.

[Andy Reichert]

Hi Andy,

 

All kit wheel makers in the UK sell the same wheels for 00 as for EM. Or at least, I don't know any who don't. Some of them, e.g. Alan Gibson, set them at 14.8mm back-to-back for DOGA Fine (on which they are ok) but fail to mention that they won't run on 00-BF or Peco (they are too narrow).

 

That's the primary reason for adopting "EM minus 2" (00-SF) -- it allows these EM wheels (ideally closed up to 14.6mm back-to-back) and unmodified RTR wheels to run on the same track. If Tony Wright was to adopt 00-SF he would discover this for himself.

 

regards,

 

Martin.

 

I agree with you and earlier mentioned gauge narrowing as a solution in my reply, but it doesn't help people who already have a lot of correctly described 16.5 mm gauged track laid.

 

It's not the same issue as Terry Flynn's though.

 

Andy

[martin_wynne]

Post # 39 as I said before - Precis - Min radius is caused by  equipment. So is the same both 00 and 00-SF.

 

Well it could be. For example if the swing of a pony truck has restricted clearance behind cylinders, or a coupling is not long enough in relation to the length of side buffers, or working corridor connections are used, or front overhang conflicts with a platform clearance, or lots of other things. Changing the track gauge won't affect such radius limitations.

 

This AMRA radius page does refer to matters such as buffers, bogie swing etc. But I suspect that its relevance to UK-outline models is rather limited:

 

 http://www.amra.asn.au/minimumradius.pdf

 

but it doesn't help people who already have a lot of correctly described 16.5 mm gauged track laid.

 

Well self-evidently if something isn't working there isn't a magic wand which anyone can wave to make it work.

 

However, one very big advantage of 00-SF is that you can convert an existing 00 layout to 00-SF one turnout at a time and continue running, because it doesn't require any changes to the wheels. Unlike for example changing to DOGA-Fine, EM, P4, etc., all of which are all or nothing changes.

 

I don't know what you mean by "correctly described" 16.5 mm gauged track. If it measures 16.5mm who is going to describe it as anything else? Your posts really can be a puzzle to understand sometimes.

 

Martin.

[The Bigbee Line]

I'm confused here. I read the thread to learn something. All I've learned is people should use PMs if the disagree so vehemently.

Wish I hadn't bothered........